Food loaves come in a variety of shapes (round, square, rectangular, oval, etc.), cross-sections, and lengths. Such loaves are made from various comestibles, such as meat, cheese, etc. Most loaves are provided to an intermediate processor who slices and packages the products in groups for retail. The groups are precisely weighed before packaging.
A variety of machines have been developed to slice such loaves. Such machines include the FX180™ and the FX Plus™ available from Formax, Inc., of Mokena, Ill., USA. The aforementioned machines are high speed food loaf slicing machines that slice one, two, or more food loaves simultaneously using one cyclically driven slicing blade.
In the aforementioned machines, the food loaf slices are received in groups of predetermined weight on a receiving conveyor that is disposed adjacent the slicing blade. The receiving conveyor receives the slices as they are cut by the slicing blade. In many instances, neatly aligned stacked groups are preferred and, as such, the sliced product is stacked on the receiving conveyor. In other instances, the groups are shingled so that a purchaser can see a part of every slice through a transparent package. In these other instances, conveyor belts of the receiving conveyor are gradually moved during the slicing process to separate the slices. The stacked or shingled slices are transferred from the receiving conveyor onto a deceleration conveyor, and then transferred onto a weigh scale conveyor.
FIG. 1 illustrates a prior art food loaf slicing machine 50 in detail. The slicing machine can be a high speed slicing machine such as disclosed in U.S. Pat. Nos. 6,484,615; 5,628,237; 5,649,463; 5,704,265; 5,724,874; herein incorporated by reference.
Slicing machine 50 comprises a base 51 that is mounted upon four fixed pedestals or feet 52 (three of the feet 52 appear in FIG. 1) and has a housing or enclosure 53 surmounted by a top base 58. Base 51 typically affords an enclosure for a computer 54, a low voltage supply 55, a high voltage supply 56, and at least one scale mechanism 57. Base enclosure 53 may also include a pneumatic supply or a hydraulic supply, or both (not shown).
The slicing machine 50 may include a conveyor drive 61 utilized to drive an output conveyor/classifier system 64.
The slicing machine 50 of the illustrated embodiment further includes a computer display touch screen 69 in a cabinet 67 that is pivotally mounted on and supported by a support 68. Support 68 is affixed to and projects outwardly from a member 74 that constitutes a front part of the housing of slicing station 66.
Referring first to conveyor/classifier system 64 at the left-hand (output) end of slicing machine 50, the system 64 includes an inner stacking or receiving conveyor (not shown) located immediately below slicing station 66. The receiving conveyor is sometimes called a “jump” conveyor. From the jump conveyor groups of food loaf slices, stacked or shingled, are transferred to a decelerating conveyor 131 and then to a weighing or scale conveyor 132. From the scale conveyor 132 groups of food loaf slices move on to an outer classifier conveyor 134. On the far side of slicing machine 50 the sequence is substantially the same.
Machine 50 produces a series of stacks 92 of food loaf slices that are fed outwardly of the machine, in the direction of the arrow A, by conveyor classifier system 64. For a dual loaf slicing machine, the machine 50 also produces a series of stacks 93 of food loaf slices that move outwardly of the machine on its output conveyor system 64 in the direction of arrow A.
A loaf feed mechanism 75 drives the loaves into the slicing station 66 where they are sliced by a rotating knife blade. The thickness and total weight of the slices are controlled by the computer 54 which actuates various mechanical components associated with the slicing operation. The slicing thickness and total weight for each sliced group are programmed though the touch screen 67 which interfaces with the computer 54. As the blade slices the loaves, the slices are deposited on the jump conveyor where the proper numbers of slices are either stacked or shingled. The jump conveyor then drives the slice groups to the deceleration conveyor 131.
FIG. 2 shows a weigh scale arrangement 57 of the prior art. For the machine 50 described in FIG. 1, two scale arrangements 57, side-by-side would be used, one for each series of stacks 92, 93. The operation of the scale arrangement and a conveyor/classifier system for a high speed slicing machine is described in detail in U.S. Pat. No. 5,704,265, herein incorporated by reference.
The scale includes a plurality of grids or fins 206 that are arranged in parallel with each one interspersed between adjacent belts 208 of the conveyor 212. The grids 206 are connected to a plate 232 which is connected to a rod 238 by a fastener 237 extending through the rod 238 and threaded into a threaded bore 239 of the rod 238. Alignment pins 207 are used to ensure a single reattachment orientation of the plate 232 to the rod 238. The rod 238 is connected to a load cell 242 by a long fastener 244 countersunk in the bore 239. The load cell 242 is located beneath the top base 58 of the slicing machine cabinetry. Once a stack or draft of cuts slices 218 is positioned above the grids 206, the conveyor 212 is lowered (as shown for example in FIG. 4) by a pneumatic actuator 226 wherein the grids 206 extend upwardly of the belts 208 and assumed support of the draft 218. The weight of the draft 218 is transferred through the grids 206 and rod 238 to the load cell 242. A weight measurement signal is sent by the load cell to machine control.
It is important that food material not enter into the machine cabinetry beneath the top panel. The machinery inside the cabinetry is not routinely sanitized and is more difficult to sanitize. The rod penetrates through the top base 58 of the machine cabinetry. An effective seal between the rod 238 and the top base 58 is required. However, to ensure accurate weight measurements, the rod 238, and parts connected to the rod, cannot touch the slicing machine cabinetry and thus cannot be sealed in a contacting manner to the top base 58, i.e., the rod 238 must have zero friction vertical movement.
Between the plate 232 and the rod 238 is a shroud 240 that over fits a cover 241. The cover 241 is drawn tightly against the top base 58 by a lock ring 253 threaded onto an open bottom end of the cover 241.
Within the cover 241 is an annular cap 255 mounted to the rod 238 that extends over an opening 257 of a drip pan 259. The drip pan 259 is mounted to an underside of the top base 58. Any liquid collected in the drip pan 259 is directed to a drain outlet 261 and thereafter by tubing to a drain outside of the machine cabinetry.
Thus, to provide a sealing of the penetration of the rod 238 through the top base 58, the shroud 240 helps to prevent spray from entering the cover 241. The cap 255 helps to prevent any spray that enters the cover 241 from entering the central opening 257 of the drip pan 259. Any spray deflected by the cap 255 is intended to collect in the drip pan 259 and be removed to a drain. The shroud 240 and cap 255 move vertically with the rod 238 but do not touch the cover 241 or the drip pan 259 which are fixed to the top base 58 of the slicing machine cabinetry.
In the meat slicing facility, portions of the slicing machine 50 above the top base 58 that are exposed to meat and spray are typically dismantled for a thorough cleaning and sanitizing with water and sanitizer every day (or sometimes more often during the day). Often times the slicing machine will also be cleaned or rinsed off during daily production between thorough cleanings and sanitizing.
FIG. 3 shows the scale arrangement configured for the thorough cleanings. The grids 206 and plate 232 are removed for separate cleaning, by removal of the fastener 237. A temporary closure 260 is threaded onto the rod 238 using a hand screw 264. The closure 260 includes a seal element 266 that seals against the scale cover 241. Once in place, the temporary closure is effective in preventing any wash water, food particles and sanitizer from penetrating beneath the top base 58.
However, it is possible that a sanitizing worker forgets, or disregards putting the temporary closure 260 in place for the thorough cleaning. Also, for mid-day rinsing or cleaning, between thorough cleanings, no temporary closure is usually installed. As can be seen, without the temporary closure in place, water, sanitizer and potentially meat products have a direct path “P” into the slicing machine cabinet beneath the top base 58. Alternatively, without the temporary closure in place water, sanitizer and potentially meat products have a direct path “Q” into the slicing machine cabinet beneath the top base 58 by overflowing the drip pan 259.
The present inventors have recognized that it would be desirable to improve the operability, cost and sanitation of weigh scales for food product production.